1. Field of the Invention
The present invention relates to an image forming apparatus having an image forming portion based on the electrophotographic system and an image forming portion based on the inkjet system.
2. Description of the Related Art
General conventional methods for obtaining an image include the method based on the electrophotographic system (toner type) and the method based on the inkjet system (ink type). These two methods (recording systems) have their own respective advantages. The electrophotographic system can achieve fast speed, and the inkjet system exhibits excellent ink color reproduction. Apparatuses which selectively use such respective advantages so as to form an image have been proposed.
For example, Japanese Patent Laid-Open No. 2002-301838 implements an apparatus which selectively uses such respective advantages so as to form an image, by disposing an image forming portion based on the inkjet system downstream from an image forming portion based on the electrophotographic system.
However, the conveying path of the recording medium in the conventional image forming apparatus passes through the image forming portion based on the electrophotographic system and then goes to the image forming portion based on the inkjet system. Accordingly, even in a case where solely an image based on the inkjet system is to be formed, the recording medium passes through the image forming portion based on the electrophotographic system. In this case, the recording medium on which an image based on the inkjet system is to be formed passes through also the image forming portion based on the electrophotographic system. This may cause deterioration of the recording medium or the image forming portion based on the electrophotographic system.
For example, when the recording medium is special paper which is differing in type from plain paper, such as an envelope, the recording medium may be wrinkled by the fixing portion in the image forming portion based on the electrophotographic system. Further, when the recording medium is small-sized paper among those applicable sizes, the temperature may rise at part of the fixing portion in the image forming portion based on the electrophotographic system where the recording medium does not pass through. This may cause deterioration.
Further, disposition of the image forming portion based on the inkjet system downstream from the image forming portion based on the electrophotographic system brings about an increase in size of the apparatus, because such an apparatus corresponds to a construction including an image forming portion based on the electrophotographic system, to which an apparatus having an image forming portion based on the inkjet system is added.